A pair of electrode pads are used in an AED. One ends of lead wires are connected to the electrode pads, respectively. The lead wires and the electrode pads are stored in a package while being housed in a hermetically sealed state. Parts of the lead wires extend from the interior of the package to the outside together with a connector to which the other ends of the lead wires are connected.
In the electrode pads, problems such as that, when the pads are to be used, necessary electrical conduction with the living body may not be attained and the pads may not be used must be avoided. In the case where electrode pads which have been once used (hereinafter, such electrode pads are sometimes referred to as used electrode pads) are again housed in a package in a state similar to the unused state, the pads must be in a condition where they can be recognized to be unusable. Also during storage (during standby), therefore, electrode pads are always connected to an AED, and periodically automatically checked by the AED, and, when an abnormality occurs, the AED informs of the abnormality. The checking process will be briefly described. A pair of electrode pads are housed in a package in a state where gel surfaces of the electrode pads are conductive with each other. The conduction state between the lead wires is monitored, thereby checking whether the connection between the lead wires is broken or not, and the drying degree of the gel.
A configuration is known where, in order to meet the request, for example, gel surfaces of paired electrode pads are stuck together in a state where the gel surfaces are opposed to each other through a punctured release liner to attain an electrical connection, and then the electrode pads are housed in a package (hereinafter, the configuration is referred to as Configuration example 1). Lead wires are connected to the electrode pads, respectively, and parts of the lead wires extend from the interior of the package to the outside together with a connector to which the opposite electrode pad side ends of the lead wires are connected. Therefore, a conduction test can be performed by causing a current to flow from the lead wires through the pair of electrode pads stored in the housed state.
JP5113183B2 discloses electrode pads in which a conduction test is performed by forming an electrically closed loop by: a release liner including two conductive sheets which are clamped between first and second nonconductive sheets; and a clip. In the first nonconductive sheet; a first hole which is connected to a gel of the first electrode pad, and a second hole which is not connected thereto are formed, and a first hole which is connected to a gel of the second electrode pad, and a second hole which is not connected thereto are formed. The second nonconductive sheet is a single sheet in which no hole is formed.
One of the conductive sheets is placed so as to connect between the first hole which is connected to the gel of the first electrode pad, and the second hole (on the side of the first electrode pad) which is not connected thereto. The other conductive sheet is placed so as to connect between the first hole which is connected to the gel of the second electrode pad, and the second hole (on the side of the second electrode pad) which is not connected thereto. According to the configuration, the gel of the first electrode pad is connected to the one conductive sheet through the first hole, and the one conductive sheet is located in the second hole on the side of the first electrode pad. The gel of the second electrode pad is connected to the other conductive sheet through the first hole, and the other conductive sheet is located in the second hole on the side of the second electrode pad. The one conductive sheet facing the second hole on the side of the first electrode pad, and the other conductive sheet facing the second hole on the side of the second electrode pad are connected to each other by the clip, whereby the electrical connection between the first and second electrode pads can be attained, and a conduction test can be performed by causing a current to flow from the lead wires connected respectively to the first and second electrode pads.
In the electrode pads of Configuration example 1, when the pads are to be used, it is possible to avoid problems (conduction breakage and the like) such as that electrical conduction with the living body is not attained and the pads cannot be used. When, after use, the pair of electrode pads are housed in a package while the gel surfaces are opposed to each other, however, electrical conduction is obtained regardless of whether a release liner is used or not, and therefore it is impossible to detect the state where the pads have been used.
In the electrode pads disclosed in JP511313B2, as described above, a conduction test can be performed in a stored state. Even when, after use, the electrode pads are returned to the original state through the release liner and housed in the package, electrical conduction cannot be obtained unless the clip is used, and therefore it is possible to detect the state where the pads have been used. When the electrode pads are housed in the package while the gel surfaces are opposed and directly stuck to each other, however, electrical conduction is obtained, and therefore it is impossible to detect the state where the pads have been used.
As described above, conventional electrode pads have a problem in that it is impossible to completely detect a situation where used electrode pads are housed in a package.